Automatic draft-regulator for furnaces.



H. F. WESTPHAL. AUTOMATIGDRAPT REGULATOR FOR FURNACES.

APPLICATION TILED DBO. 30, 1908.

945,831, Patented Jan. 11,1910.

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INVENTOR WITNESSEQ7: v h; I 7 w ATTORNEYS.

H. F. WESTPHAL.

AUTOMATIC DRAFT REGULATOR FOR FURNACES. APPLICATION FILED DEC. 30, IQOB.

945,831 Patented Jan. 11,1910.

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AUTOMATIC DRAFT-REGULATOR FOR FURNACES.

To all whom it may concern:

Be it known that I, HERMAN F. WEST- PIIAL, a citizen of the UnitedStates, residing at Milwaukee, county of Milwaukee, and State oflVisconsin, have invented new and useful Improvements in AutomaticDraft- Regulators for Furnaces, of which the following is aspecification.

My invention relates to improvements in automatic draft regulators forfurnaces, stoves and the like, and the same is explained by reference tothe accompanying drawings, in which I Figure 1 represents a side viewthereof, part in section; Fig. 2 is a front view.

Like parts are identified by-the same reference characters in bothviews.

1 represents a length of ordinary furnace or stove pipe, which isadapted to connect a furnace or stove with the chimney or smoke flue,and which is provided near one end with an inlet air duct 2.

3 is a damper supporting sleeve.

4 is a damper, which is pivotally supported from the sleeve 3 upon thetransversely arranged rod 5. The rod 5 is supported at its respectiveends in suitable apertures formed in the opposing sides of the sleeve.To one end of the rod 5 is attached an operating arm 6, through whichmotion is communicated to said rod and damper from a spring 7. Thespring 7 is connected at one end to the wall of the sleeve and at itsopposite end to the outer end of said arm, the tension of said springbeing such as to yieldingly retain said damper in its closed position,while the resiliency of the spring will permit said damper to be readilythrown open with slight inward pressure upon one side of said dampersupporting rod. The

damper and its supporting mechanism thus far described is substantiallyof ordinary construction. 1

My heat actuating means for automatic ally opening said damper comprisesone or more expansible chambers 8, which are preferably formed of thinflexible sheet metal, in which chambers a small quantity of volatileliquid is stored. The chambers 8 are located in a separate heatingchamber 9 from the pipe 1, from the walls of which they are supported bythe open bracket 10. Each chamber is provided on its respective sideswith a separate central bearing member,

Specification of Letters Patent. Application filed December 30, 1908.Serial No. 470,015. I

Patented Jan. 11, 1910.

which bearing members are respectively indicated by the referencenumerals 11, 12, 13 and 14, whereby as the respective sides of saidchamber are moved outward by the expansive force of their contents, theywill all cooperate to force the central bearing 14 forward through thecentral aperture 15 of the inclosing cover 16. It will be understoodthat as the chambers 8 are expanded and contracted under the influenceof varying temperature in the pi e 1, the central member 14 will because to protrude a greater or less length from the chamber 9.

Motion is communicated from the protruding end of the member 14 to thedamper 4 through the lever 17. The lever 17 is piv: otally supportedfrom the bracket 18 and said bracket 18 is in turn rigidly supportedfrom, or in close proximity to, the cover 16 in any suitable manner,whereby as the short arm 18 of said lever is moved outward or away fromsaid pipe 1 by the expansive action of said chambers 8, the long arm 19of said lever is moved inward or in the opposite direction against oneside of said damper 4, whereby said damper is turned from the closedposition shown to the open position indicated by dotted lines, therebypermitting the exterior air to enter the pipe 1, whereby the draft inthe stove or furnace is checked and the combustion of fuel is retarded.As the draft is thus checked in the furnace, the expansion chambers 8will be proportionately cooled, whereby their contents is contractedwhen said chambers will be caused by their own resiliency to contract totheir normal size, thus relieving the pressure upon the short arm ofsaid lever, whereby the pressure of the long arm against said damperwill be Withdrawn. When the pressure of the arm 19 is thus withdrawnfrom the damper 4, said damper will be brought back to its normal closedposition by the recoil of the spring 7. Thus it will be obvious that thedamper is automatically opened as the temperature in the system risesthrough the expansion of the chambers 8 and is closed as the temperaturefalls by the recoil of said spring. For convenience of adjustment, thelever 17 is preferably formed in two parts, 18 and 19, Which areadjustably connected together, the arm 18 being provided with aprojecting lug 20 through which an aperture is formed for the recepbythe set screw 21, which has screw threaded bearings in said lug 20.

To make the damper actuatlng mechanism more or less sensitive to thechanges of temperature, I have provided the short arm 18 with an an ularcam 22, which is revolubly connected with the underside of said lever bythe pin 23, and said cam is provided with an operating handle 24, bywhich said cam is turned upon its supporting pin. Thus it will beunderstood that when the cam is adjusted with its widest end 25 abovethe central projection of the expansion chamber,

said lever will be actuated more promptly by the expansion of saidchambers 8. When however said cam 22 is reversed so as to bring itsnarrow end above the' central projection, said lever will be acted uponless promptly and consequently a higher temperature will be required inthe furnace and furnace pipe to actuate said, lever and draftcontrolling damper. From this fact, it will be understood that when theweather is exceedingly cold, a higher temperature may be maintained inthe furnace. When however the weather is mild, the heat regulatingdevice may be adjusted, by reversing the movement of. the cam, so thatthe damper will be opened and closed with but slight variation oftemperature around the expansion chambers.

While I have shown two expansion chambers supported from the bracket 10,for some purposes a single chamber may be substituted therefor, or thenumber of said chambers may be increased as circumstances may require.To prevent the liability of the expansion chambers or cooperating partsfrom being injured by too great expansion, said expansion chambers arepreferably yieldingly supported from the bracket 10 by a splral spring26, which is interposed between the central member of the bracket 10 andthe opposing side of the expansion chamber, the tension of spring 26being such as to permit said chambers under excessive expansion to movedownward or toward the central member of said supporting bracket 10.While the long arm 19 of the lever 17 may, if desired, be used in directcontact with the damper 4, I preferably interpose a bracket 27, which isrigidly affixed to said damper and I also preferably provide the end ofsaid arm 19 with a friction bearin roller 28, whereby as said arm 19 ismove downwardly or toward the damper 4, the frictional contact will notonly be reduced, but the ressure of said arm 19 will be more efiective yapplied to said damper, as the same is turned from the closed positionshown to the open position indicatedby dotted lines.

and while aplurality of expansion chambers are preferably employed foractuating the damper, a single chamber of suflicient size may besubstituted therefor.

Having'thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

- 1. The combination of a furnace pipe provided with an inlet air duct,a damper pivotally supported in said duct and adapted to control thepassage of exterior airthrough the same, a heating chamber formed inconnection with said furnace pipe, an expansion chamber located in saidheating chamber, an expansible fluid located in said expansion chamber,a central member bearing at one end against said expansion chamber andextending throughan aperture provided therefor in the walls of saidheating chamber, a lever pivotally supported in close proximity to saidheating chamber, one arm of which is adapted to contact with theprotruding end of said central bearing member, while its opposite end isadapted to contact with an integral part of said damper, whereby as.said expansion chamber is expanded or contracted by the fluid containedtherein, motion will be communicated therefrom through said centralmember and lever to said pivotally supported damper, and where by themovement of said damper is controlled through the action of saidexpansion chambers.

2. The combination of a furnace pipe provided with an inlet air duct, adamper pivotally supported in said duct and'adapted to control thepassage of exterior air through the same, a spring for closing andretaining said damper in its normal position, a heating chamber formedin connection with said furnace pipe, one or more expansion chamberslocated in said heating chamber, an expansible fluid located in said e'xansion chamber or chambers, a lever pivota ly supported with one end inclose proximit to said expansion chamber and adapted to ear otallysupported in said duct and adapted to control the passage of exteriorair through the same, means for retaining said damper in its normalposition, a. heating chamber formed in connection with said furnacepipe, one or more expansion chambers located in said heating chamber, anexpansible fluid located in said expansion chamber or chambers, a leverpivotally supported with one end in close proximity to said expansionchamber and adapted to bear at its opposite end against said damper, anadjustable contact bearing interposed between said lever and expansionchamber adapted to be manually changed to accelerate or retard theaction of the damper.

4:. The combination of a furnace pipe provided with an inlet air duct, adamper pivotally supported in said duct and adapted to control thepassage of exterior air through the same, a contact bearin plate formedat an angle to the front of said damper, means for retaining said damperin its normal position, a heating chamber formed in connection with saidfurnace pipe, one or more expansion chambers located in said heatingchamber, an expansible fluid located in said expansion chamber orchambers, an adjustable lever pivotally supported with one end in closeproximity to said expansion chamber and adapted to bear at its oppositeend against said angular contact bearing.

5. The combination of a furnace pipe provided With an inlet air duct, adamper pivotally supported in said duct and adapted to control thepassage of exterior air through the same, a spring for closing andretaining said damper in its normal position, a. heating chamber formedin direct connection with said furnace pipe, a plurality of expansionchambers located in said heating chamber, an expansible fluid located insaid expansion chamber or chambers, an adjustable lever pivotallysupported with one end in close proximity to said expansion chamber andprovided atits opposite end with an anti-friction roller bearing,adapted to bear against said damper, whereby as one end of said lever isactuated by the expansive force of the fluid in said expansion chambers,the opposite end of said lever will be caused to open said damper andwhereby as said lever is moved in the opposite direction, the damperwill be closed by said s ring.

In testimony whereof I a x my signature in the presence of twowitnesses.

HERMAN F. WESTPHAL.

Witnesses:

JAS. B. ERWIN, O. R. E/RWIN.

